The present invention relates generally to an apparatus for elevator cars and, in particular, to an apparatus for preventing drift of an elevator car when stopped at a floor.
The European patent specification 0 578 238 shows a stopping device for an hydraulic elevator for preventing the downward drift of a the elevator car. A pair of magnetically actuated latches swivel outwardly at a carrier frame of the elevator car. Stop blocks are positioned on the elevator shaft wall and extend into the paths of the actuated latches so that the latches contact the stop blocks to prevent downward movement of the elevator car.
A disadvantage of the above described equipment is that the latches require a complicated magnetically actuated linkage to swing outwardly and retract. Thus, the reliability of the stopping device is impaired. At low car loads, the danger of upward drift exists since the actuated stopping device does not prevent upward movement.